Personally, I don't think his name was Graiper. It just doesn't fit.
The original poster inquires about this subject on the "Find a grave forums".
He was killed in action on July 21, 1918, and published casualty lists in American newspapers claimed he was from Opale, Russia.
...
I cannot find an Opale, Russia, but I found an Opole, Poland.
Hmm, let us run with the following hypotheses:
1. His original name was actually Gräper. The a-umlaut Ä is often represented by AE. So the alternative spelling would be Graeper. Nowhere in OP messages the soldier's nationality is mentioned. He could be equally well Polish, German or Silesian.
2. How does Graeper sound in German? To my untrained ear it sounds close enough to Polish "griepa" or English "graipa". I checked it via translate.google.com and ivona.com .
3. What if the American newspapers misprinted: "Oppeln, Prussia" or "Opole, Prussia" into "Opale, Russia"? Apparently Opole is spelled Uopole in Silesian.
4. Graeper (Gräper) is quite a popular German name - 770,000 google results
5. There are 3,500 google results for Graeper Oppeln
6. There are 1,700 google results for Graeper Opole
7. A list of killed during WWI, polegli.tgcp.pl/polegli.php?lng=en&id=G&order=mp&sort=d, contains one record with the same last name: Oskar Graeper, Mikołajki, Warmian-Masurian Voivodship
The same game could be played with u-umlaut, Grueper. Its German pronunciation could also lead to confusion. I hear here a sound like a Polish "gripa". But Grueper looses to Graeper statistically: there are only 3,500 google results vs. 770,000 for the former.
Does it make any sense to you?
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German graeper => English graper:
In the fifteenth century, the roughened or studded gripe of the lance.
n. The ring or hollow cylinder of iron through which the shaft of a lance passes and by which it is seized.